How Does a Forklift Work

Forklifts use a combination of hydraulics, a pulley system and other things to lift heavy materials across different distances. They are commonly used in warehouses, construction sites and other places that need to transport lots of heavy materials. We know where it’s used, but how does a forklift work? To answer that, we put together this guide to break down what a forklift is used for, its different parts and how it works.

What Is the Purpose of a Forklift?

A forklift is mainly used to carry heavy loads across long distances of varying terrain. It’s useful for projects that require lots of materials in various places and cuts down the time and effort needed to lift, carry and transport.

What Are the Main Parts of a Forklift?

A forklift can lift lots of weight without tipping over, thanks to its design. Each part is crucial to keep the functioning and operators safe while operating a forklift. These parts vary depending on the model. For example, some forklifts are more suited for rugged terrain while others are not. These are the basic parts of most forklifts:

parts of a forklift

  • Load back-rest: This part keeps the load from shifting backwards.
  • Overhead guard: This section of the forklift protects operators from a load if it falls.
  • Carriage: The carriage is the base of the forklift and is fixed on mast rails to easily move up and down.
  • Forks: These are the prongs that carry loads.
  • Mast: The mast raises and lowers the load. It also has interlocking rails that provide horizontal control.
  • Counterweight: This weight is used to stabilize the forklift and keep it from tipping over.
  • Power source: Forklifts can be powered by things like fuel cells, propane gas, gasoline, diesel engine or batteries.
  • Truck frame: The frame is the base of the machine and all parts are attached to it.
  • Tires: Forklifts can use pneumatic tires (normally used outdoors) or solid tires (sometimes called cushion tires) that are used both indoors and on hard, flat surfaces.

The most important parts of the forklift are the hydraulic system, chain pulley system and the forklift controls. Both systems and the controls are vital for the forklift’s power and lifting abilities. We’ll dive into each part below.

How Does the Forklift Hydraulic System Work?

The hydraulic system uses a series of cylinders, pistons and fluids to efficiently lift and lower forklift loads. The hydraulic pistons are attached to the forklift’s masts.

Parts of the Hydraulic System

Here are a few parts of the forklift’s hydraulic system to familiarize yourself with before understanding how it works:

  • Lift handle: Operator pushes this to lift or lower the forklift’s load. This handle is connected to a pump found at the machine’s base.
  • Pump: When activated, it pushes fluid through a tube leading to both hydraulic cylinders.
  • Hydraulic cylinders: These are composed of a hollow tube that is shut on one end to trap fluids. A movable, lubricated piston is equipped on the other end.

Here’s how the hydraulic system works:

how forklift hydraulics work

1. Fluid enters the hydraulic cylinder through a special valve that allows it to enter without it escaping. Pressure increases as fluids increases in the cylinder.

2. Net upward force is created when pressure is applied across the area of the piston head.

3. The piston moves up as a result of this upward force. This increases fluid and decreases pressure.

4. Physical equilibrium is automatically achieved at this point when, at a given lift height, the fluids’ force is equal to the forklift load’s downward force.

How Does the Forklift Roller Chain Pulley System Work?

The machine’s forks that carry the load are attached to the frame with a pair of roller chain pulleys. The pulley’s fulcrum is a gear found at the top of the mast.

Here’s how the roller chain pulley system works:

how the chain pulley system works

1. Hydraulic pistons push the masts up.

2. Gears on the mast pushes against the roller chains.

3. The masts move up and pulls the fork up.

4. One side of the chain is attached to the immovable frame of the forklift, so masts can only move up if the gear rotates clockwise and pulls the forks up.

Since one side of the chain is attached to the immovable frame of the forklift, that masts can only move up if the gear rotates clockwise and pulls the forks up.

This system allows the fork to lift higher than it would if the forklift relied solely on the hydraulic system. If it only used hydraulics, the forklift would need taller cylinders to reach the same height. Taller cylinders require more materials, stronger pumps and higher pressure limits that can shift the forklift’s center of gravity, increase the risk of tipping and overall increase the level of danger when using forklifts.

Forklift Controls

A forklift’s main controls are for steering and lifting. Although it sounds simple, understanding how both of these work helps an operator safely and efficiently get the job done.

forklift steering and lifting controls

Steering Controls

The steering controls are similar to ones you’d find in a golf cart or a regular car. A forklift has an acceleration pedal, break, steering wheel, forward gear and reverse gear. However, forklifts use rear-wheel steering, meaning that the steering wheel controls the wheels in the rear. This works better for forklifts since operators have greater precision and rotation control when carrying a load.

Lifting Controls

The lifting controls use one lever for moving the load up and down and another for tilting the load back and forth. Pushing the lifting lever forward moves the load up while moving it backwards moves it down. Tilting, however, is a bit more complex.

The tilt function involves two more hydraulic cylinders found at the base of the masts. Here’s what happens when the tilt lever is moved in both directions:

  • Forward: Air is pumped into the chamber. The rise in pressure level pushes the piston head and results in the mast tilting away from the frame.
  • Back: Air is gently released from the chamber and air is pumped in the other pair of cylinders we mentioned earlier from the hydraulic system. The masts lean towards the vehicle when those pistons push that pair of cylinders forward.

Forklift Types and Uses

There are many different types of forklifts to choose for your project. The various types of power used, terrain, weight capacity and many other features contribute to this equipment’s versatility. In addition to warehouses and construction sites where you typically see forklifts, you can also find them at dockyards and recycling operations.

Here are a few common ways forklifts are used:

  • Construction sites: Carry building material across long distances and rough terrain
  • Warehouses: Unload and load trucks to store goods in a warehouse
  • Recycling operations: Unload recycling materials and transport to their respective sorting areas
  • Dockyards: Load girth materials on and off ships and barges, especially when swift loading is needed
  • Snow plows: Clear away snow when using a special attachment

Forklifts are great pieces of heavy equipment to carry and transport materials across the work site with little to no effort. Check out our wide selection to see which machine works best for your project.